The participation of Senator John Glenn of Ohio in shuttle mission STS-95 made it the most ballyhooed space flight since the Apollo moon landings. Millions of television viewers watched the liftoff of the shuttle Discovery and avidly followed the progress of the nine-day mission. Glenn even made a guest appearance, via radio link, on the Tonight Show. The public was clearly delighted to see the former Mercury astronaut--the first American to orbit the earth--return to space at the age of 77. And the publicity was a much needed shot in the arm for the National Aeronautics and Space Administration, which is now starting work on the controversial International Space Station.
But the stated goal of STS-95 was not publicity; Glenn's primary role was to serve as a guinea pig in a barrage of medical experiments, most of them designed to study the connections between space flight and aging. The results of those tests won't be released for several months, but scientists already know that the studies will not yield any conclusive findings. The problem with the experiments is that they involved just one elderly subject: Glenn himself. To draw reliable conclusions, researchers must be able to compare Glenn's data with tests on other senior citizens in space. But NASA has no plans to send any more septuagenarians into orbit.